A level indicator device is disclosed for use in conjunction with a road vehicle such as a caravan, trailer, motor home or mobile crane and which comprises an electrically energized level sensor that is arranged to provide an output signal that is representative of a prevailing level of the sensor, a signal generator associated with the sensor and arranged in use to generate a signal that is representative of a substantially horizontal level when that level is sensed to prevail by the sensor. A radiofrequency signal transmitter is located in circuit with the signal generator and is arranged to transmit a radiofrequency signal that is modulated by the signal generated by the signal generator, and a remote receiver is provide and is arranged to receive and demodulate the radiofrequency signal. In one embodiment of the level indicator device the level sensor comprises a MEMS accelerometer that measures G-force in plural axes. Also disclosed is a vehicle level adjusting system for a road vehicle and which comprises a level indicator device as defined and a plurality of level adjusting devices, in the form of ramps or jacking actuators, that are arranged to effect levelling of the vehicle.
Legal claims defining the scope of protection, as filed with the USPTO.
1. A level indicator device for use in conjunction with a road vehicle and which comprises: an electrically energised level sensor comprising an accelerometer that measures G-force in at least three axes and that is arranged to provide an output signal that is representative of a prevailing level of the sensor, a signal generator associated with the sensor and arranged in use to receive the sensor output and, in response thereto, to generate signals that are representative of prevailing inclination of the sensor in orthogonal directions and that are representative of a substantially horizontal level when that level is sensed to prevail by the sensor, the signal generator able to be calibrated in order to generate said signals when the device is mounted in either a generally horizontal or a generally vertical orientation, a radiofrequency signal transmitter located in circuit with the signal generator and arranged to transmit a radiofrequency signal that is modulated by the signal generated by the signal generator, and a remote receiver that is arranged to receive and demodulate the radiofrequency signal and to display indications of the prevailing inclination or horizontal level of the sensor.
2. A level indicator device as claimed in claim 1 wherein the level sensor and the associated signal generator are, in use, mounted to the road vehicle.
3. A level indicator device as claimed in claim 1 wherein the remote receiver comprises a hand-held device.
4. A level indicator device as claimed in claim 1 wherein the remote receiver comprises a fixed position device which, in use, is located within a towing vehicle for the road vehicle or in a drive cabin of a unitary said road vehicle.
5. A level indicator device as claimed in claim 1 , wherein the signals generated by the signal generator are fed to the radiofrequency transmitter and wherein the transmitter is arranged to frequency modulate a carrier signal that, in use, is radiated by the transmitter.
6. A level indicator device as claimed in any claim 1 , wherein the sensor comprises a micro-controlled electro-mechanical (MEMS) accelerometer.
7. A level indicator device as claimed in claim 1 wherein the signal generator is arranged to generate a signal that is representative of a substantially horizontal level when, in use, the output signal from the level sensor is representative of a level within the range of (0°+/−5°).
8. A level indicator device as claimed in claim 1 wherein the signal generator is arranged to generate a signal that is representative of a substantially horizontal level when, in use, the output signal from the level sensor is representative of a level within the range of (0°+/−<0.5°).
9. A level indicator device as claimed in claim 1 wherein the remote receiver incorporates a display device comprising a network of five light emitting diodes (LED's), which are arranged to be biased into conduction to display the indications of the inclination or horizontal level of the sensor.
10. A level indicator device as claimed in claim 9 wherein the remote receiver comprises a radiofrequency receiver stage that is arranged to detect for a modulated radiofrequency transmission that is, in use, radiated by the transmitter, the receiver stage being located in circuit with a driver and the associated display device.
11. A level indicator as claimed in claim 10 wherein the signal generator incorporates a display device comprising a network of five LED's that are arranged to display indications of the prevailing inclination or horizontal level of the sensor corresponding to those displayed by the remote receiver.
12. A vehicle level adjusting system for a road vehicle and which comprises a level indicator device as claimed in claim 1 and a plurality of level adjusting devices that are arranged to effect levelling of the vehicle in an east-west direction, the level adjusting devices comprising ramps up which the vehicle may be maneuvered to adjust the vehicle level to a substantially horizontal disposition.
13. A vehicle level adjusting system for a road vehicle and which comprises a level indicator device as claimed in claim 1 and a plurality of level adjusting devices that are arranged to effect levelling of the vehicle, the level adjusting devices comprising jacking actuators which are positioned and actuatable to effect levelling of the vehicle to a substantially horizontal disposition.
Cooperative Patent Classification codes for this invention. Click any code to explore related patents in that topic.
March 21, 2013
August 23, 2016
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